Yeah, I think it took me about 45 minutes to do the entire thing, and that was with a pause in the middle to sit for a bit, peruse the map I'd just bought, and drink some water. I would expect to be able to get it down to 30-40 minutes; the toughest parts are going to be navigating the cross-streets, I think. At least until I get more confident about those.

The most I've ever biked in a single day, though, is 18 miles.